The invention comprises a system for processing seismic data to estimate time shift resulting from velocity anisotropy in the earth’s subsurface. The illustrated embodiment of this invention includes an outer tube with a plurality of locking pin holes and a means for attachment to a crank arm, an inner rod housed coaxially within the outer tube and having a means for attachment to a pedal and a means for adjustably positioning the inner rod within the outer tube. The temperature probe also includes a capacitance sensor disposed on one of the handle and the shaft, the capacitance sensor configured to measure a change in capacitance when positioned proximate a conductor. The disclosed device and methods of use enjoy substantial benefits over the prior art, including simplicity of use by an operator, rapid in situ determinations of one or more analytes, and single-use methodology that minimizes the risk of contamination of both operator and patient.